The invention relates, generally, to water softeners and, more particularly, to a system and method for anticipating salt depletion.
Domestic water softeners remove hardness from raw water by passing it through a tank containing a liquid treatment medium bed, typically formed of resin beads. A salt solution, that is brine, is passed through the resin bed to restore its softening capacity. The brine is formed in a container which is connected by a liquid flow passage to the tank containing the resin beads. The flow of liquid through the liquid flow passage is regulated by a control valve which is actuated by an electronic regeneration control circuit.
Salt, typically in the form of chunks or pellets, is placed in the container. Under the control of the electronic regeneration control circuit, the control valve allows a predetermined amount of water to enter the container. Provided enough salt is present, the water and salt form a saturated salt solution, or brine, which is the regenerant for the resin bed. Again, under the control of the electronic regeneration control circuit, the control valve is actuated to cause the brine to be withdrawn from the container and circulated through, and thereby regenerate, the resin in the tank.
The amount of salt remaining in the container is reduced each time a portion of the salt is dissolved to form a regenerant. The supply of salt will become exhausted after a number of regeneration cycles, unless additional salt is placed in the container. Such that the salt supply will not become exhausted, it is desirable to provide some type of alarm to indicate that the salt supply is close to being exhausted. Such an alarm may be formed as a part of the electronic regeneration control circuit.
U.S. Pat. No. 5,363,087 is assigned to the instant assignee and discloses an example of an apparatus which detects a low level of salt and generates a corresponding low salt level alarm and is incorporated herein by reference. U.S. Pat. No. 5,363,087 discloses an apparatus for providing a regeneration solution to a regenerable liquid treatment medium bed including an electronic regeneration control circuit for controlling the regeneration of a liquid treatment medium bed with regenerant solution formed in a container by dissolving a quantity of solid material in a liquid. The container in which the regenerant solution is formed is provided with indicia spaced apart in a vertical direction. The indicia are observable with respect to the top surface of the quantity of solid material received in the container. An electronic control circuit includes a manual input means for entering the amount of solid material available in the container in terms of the observed indicia most closely corresponding to the top surface of the solid material. The electronic control circuit includes means for electronically reducing, each time a quantity of regenerant solution is used to regenerate the liquid treatment medium, the electronically stored indication of the amount of solid material remaining in the container. The apparatus includes an alarm means which is actuated to provide an alarm when the electronically stored indication of the amount of solid material remaining in the container is less than a predetermined minimum amount.
U.S. Pat. No. 5,544,072, incorporated herein by reference, is assigned to the instant assignee and discloses a method for regeneration of a water softener including a method to determine when a regeneration should occur.
The prior art systems indicate or warn when a water softener unit is low or out of salt. A user must be ready to immediately replenish the salt supply, lest there be an interruption of service. A user must provide an overstock of salt in order to avoid such an interruption of service. An interruption of service maybe an inconvenience, but also carries a greater significance if the softener has been used to remediate any health effects such as the removal of barium or radium that may be in the water being treated.
It is an object of the present invention to provide a water softener with the ability to more accurately provide the status of the amount of remaining salt and avoid interrupted service.
It is a further object of the invention to provide a water softener which anticipates when salt should be added.
It is still a further object of the invention to provide a water softener which provides a user with an indication, in advance, when salt will be required.
Accordingly, the present invention provides a method of anticipating salt depletion in a brine tank of a water softener system, the system including a controller having a user interface and display, the method comprising the steps of (a) tracking salt usage; (b) determining the amount of salt remaining in the brine tank; (c) calculating the number of days before salt is required in the brine tank based on salt usage and the amount of salt remaining in the brine tank; and (d) providing an indication of the number of days to empty, whereby a user is able to anticipate the need to replenish the salt supply and plan accordingly to assure continuous satisfactory operation of the water softener system.
In one embodiment, the method of tracking salt usage includes tracking the average salt per regeneration, the average number of days between regeneration and the number of days since the last regeneration. The salt level value of step (a) is received via a user entering the value into the system via a user interface. The step of determining or recalculating the number of days before salt is required in the brine tank is based on the salt level value is done using the formula, A/B*Cxe2x88x92D, wherein:
A=the salt level value;
B=the average salt per regeneration;
C=the average days between regenerations; and
D=the number of days since the last regeneration.
The present invention also provides a system for anticipating salt depletion in a brine tank of a water softener, the system having means for tracking salt usage; means for determining the amount of salt remaining in the brine tank; means for calculating the number of days before salt is required in the brine tank based on salt usage and the amount of salt remaining in the brine tank; and means for providing an indication of the number of days to empty, whereby a user is able to anticipate the need to replenish the salt supply and plan accordingly to assure continuous satisfactory operation of the water softener system. In one embodiment, the system includes means for recalculating the number of days before salt is required in the brine tank, in the event salt has been added to the brine tank, a regeneration has occurred, or another day has passed since the last regeneration.